This invention is in the field of cardiovascular healthcare management and patient treatment.
According to the National Cholesterol Education Program (NCEP) guidelines, low density lipoprotein (LDL) cholesterol goals and criteria for Therapeutic Lifestyle Changes and Drug Therapy in different risk categories are as follows:
The invention utilizes the health care management system described in WO 01/41037A3 to study data from patient populations for cardiovascular risk factors especially those factors related to LDL and HDL subclass. WO 01/41037AC is incorporated herein in its entirety. The text, Heart Disease Breakthrough, by Thomas Yannios, M. D. John Wiley and Son, Inc., New York, 1999 discusses management of heart disease and the role of HDL and LDL subclasses and is incorporated herein by reference.
In analyzing LDL and HDL subclass data from more than 65,000 cardiovascular patients, it has been found that indicia for patient treatment can be derived from LDL and HDL subclass information that is not available from NCEP risk factor data. Thus, the invention permits the identification of patients with healthy low density lipoprotein concentration (LDLC) and high density lipoprotein concentration (HDLC) levels who have an undesirable small dense LDL trait and deficient reverse cholesterol transport system. For example, it has unexpectedly been found that the determination of LDL III a +b permits the identification of patients who are in need of therapeutic lifestyle changes and drug therapy which are not evident from NCEP guidelines based on a conventional panel of lipid assays. Similarly HDL 2b values can be used to identify patients in need of lifestyle change or drug therapy. LDL III a+b and HDL 2b values combined is a powerful tool for identifying patients who need treatment which NCEP data indicate are not in need of treatment.
More particularly, it has been determined that cardiovascular patients with LDL III a+b levels, small dense LDL particles, of about 15% or more are in need of more aggressive cardiovascular healthcare management, i.e., lifestyle changes and drug therapy. This LDL III a+b measurement identifies about 40% of patients in need of treatment that are missed by only using NCEP guidelines. Thus, the NCEP guidelines for treatment which are based on the basic lipid panel described above are not capable of determining cardiovascular risk in a significant subpopulation of patients and result in not treating at risk cardiovascular patients.
The invention therefore encompasses a method for identifying patients with normal NCEP lipid levels who are in need of treatment for cardiovascular disease comprising measuring one or more LDL or HDL particle subtraction levels and identifying abnormal LDL or HDL subtraction levels.
LDL III a+b are the preferred LDL subclasses to be measured and HDL 2b is the preferred HDL subclass. Other factors such as lipoprotein (a) (Lp(a)), triglycerides, and homocysteine also provide highly useful information. LDL and HDL subclasses are determined by gradient gel electrophoresis (GGE), NMR, ultracentrifugation, or ion mobility analysis.